The Association for the Advancement of Medical Instrumentation (AAMI) is a professional organization in which committees are composed of representatives that include health care professionals, patients, medical device manufacturers, and representatives of federal agencies. These committees have developed voluntary guidelines for medical products and procedures. The Renal Disease and Detoxification Committee (RDD) has developed standards for dialysis equipment manufacturers and recommended practices for end users.
As stated in the AAMI objectives, the voluntary standards for a medical device recommends to the manufacturer the information that should be provided with or on the product, basic safety and performance criteria that should be considered in qualifying the device for clinical use, and the measurement techniques that can be used to determine whether the device conforms with the safety and performance criteria and/or to compare the performance characteristics of different products.
A recommended practice provides guidelines to the end user for the use, care, and/or processing of a medical device or system. This does not address device performance per se, but rather procedures and practices that will help ensure that a device is used safely and effectively and that its performance will be maintained. The documents are adopted and published in harmony with the American National Standards Institute (ANSI).
All documents developed by ANSI/AAMI are reviewed at least once every 5 years. Substantial changes may result from the review and may pose challenges to the end user in adopting the changes. For example, RD52:2004 (intended for dialysis providers) and RD62:2001 (intended for equipment manufacturers) have undergone several reviews and changes. In the years that followed, the Committee sought to harmonize with the international community to comply with the International Organization for Standardization (ISO). The harmonization resulted in significant changes to the quality, validation and methods to water and dialysate for hemodialysis as well as expanding from two documents to four (as noted). The latest documents that harmonize with ISO are:
- ANSI/AAMI/ISO 26722:2009 Water treatment equipment for hemodialysis applications and related therapies (revision of RD62)
- ANSI/AAMI/ISO 13959:2009 Water for hemodialysis and related therapies (revision of RD62)
- ANSI/AAMI/ISO 23500:2011 Guidance for the preparation and quality management of fluids for hemodialysis and related therapies (revision of RD52)
- ANSI/AAMI/ISO 11663:2009 Quality of dialysis fluid for hemodialysis and related therapies (revision of RD52)
- ANSI/AAMI/ISO 13958:2009 Concentrates for hemodialysis and related therapies (revision of RD61)
As a result of some of the challenges these standards caused to the US hemodialysis community, the AAMI RDD Committee approved and released a US deviation to the International ANSI/AAMI/ISO documents as stated above and has since published the following:
- ANSI/AAMI 26722:2014 Water treatment equipment for hemodialysis applications and related therapies
- ANSI/AAMI 13959:2014 Water for hemodialysis and related therapies
- ANSI/AAMI 23500:2014 Guidance for the preparation and quality management of fluids for hemodialysis and related therapies
- ANSI/AAMI 11663:2014 Quality of dialysis fluid for hemodialysis and related therapies
- ANSI/AAMI 13958:2014 Concentrates for hemodialysis and related therapies
The noteworthy deviation from the International Standard is found in each of the above documents. In regards to compliance with microbiological requirements, latest ISO Standards read: “Culture media shall be tryptone glucose extract agar (TGEA) or Reasoner’s 2A supplemented with 4 % sodium bicarbonate, or equivalent. Blood or chocolate agar shall not be used. Incubation temperatures of 17 °C to 23 °C, and an incubation time of 168 h (7 d) are recommended. Other test methods may also be used, provided such methods have been appropriately validated and compared to the cited methods.”
That wording has been replaced in the ANSI/AAMI 2014 Standards with the following:
“Approved culture methods shall include one of the following:
- tryptone glucose extract agar (TGEA) or Reasoner’s 2A supplemented with 4% sodium bicarbonate, or equivalent. Blood or chocolate agar shall not be used. Incubation temperatures of 17°C to 23°C, and an incubation time of 168 h (7 d); or
- Trypticase soy agar (TSA, a soybean casein digest agar) or standards method agar and plate count agar (also known as TGYE), incubated at 35°C for 48 hours.
Other test methods may also be used, provided such methods have been appropriately validated and compared to the cited methods. See USP <1231> for guidance on adoption of alternative methods.”
This deviation of test methods surrounding agar medium, incubation temperature and incubation time was not adopted by ISO, but is now found within the latest ANSI/AAMI 2014 documents as a deviation. The microbiological requirements for water as stated in 13959 remain unchanged between the two standards groups:
| Microbiological Level | Water Standard | Water Action Level |
| Colony Forming Units | < 100 CFU/mL | ≥ 50 CFU/mL |
| Endotoxin Units | < 0.25 EU/mL | ≥0.125 EU/mL |
Furthermore, there are no changes to the maximum level of chemical contaminants that can be found in product water used for hemodialysis and related processes. Keep in mind that the changes in the AAMI documents remain as voluntary requirements and are not enforceable unless the governing body Centers for Medicare and Medicaid Services (CMS) adopts the updated document as reference. As of October 2008, the CMS ESRD Interpretive Guidance references the RD52:2004 and RD62:2001 documents for ANSI/AAMI and surveyors inspect provider’s clinics and facilities based on those writings. Please note that surveyors and inspectors will measure provider’s compliance to the Quality Assurance Program or Policies that they are adhering to within their practice.
The AAMI RDD recommendations are a result of expert consensus on how to safely handle water and concentrates and for the production and monitoring of dialysate for hemodialysis. It is also intended as a guide for physicians, and particularly the directors of dialysis facilities. The standards are an invaluable source of information and policy guidance that seeks to ensure patient safety while promoting technological advancements.